Superman Returns: The Videogame

Cheat mode
Pause the game to display the "Fortress Of Solitude" menu. Then, enter one of the following codes at this menu to activate the corresponding cheat function. If you entered the code correctly, you will hear the sound of an explosion. Note: Some codes cannot be enabled until level 3 has been completed.

Play as Bizarro in Free Roam mode
Pause the game and press Up, Right, Down, Right, Up, Left, Down, Right, Up. Then, fly to the marker at the top of the GNN building to change to Bizarro. To change back to Superman, go to the marker at the other end of Metropolis.

Infinite city health
Pause the game and press Circle, Right, Circle, Right, Up, Left, Right, Circle.

All power-ups
Pause the game and press Left, Circle, Right, Circle, Down, Circle, Up, Down, Circle(3).

All bonuses
Pause the game and press Left, Up, Right, Down, Circle(3), Up, Right, Circle to unlock all bonuses.

Alternate costumes
Successfully complete the indicated task to unlock the corresponding costume:

Golden Age suit: Save Metropolis from the tornadoes
Pod suit: Defeat Bizarro

Trophies
Successfully complete the indicated task to unlock the corresponding trophy:

Bizzaro Unchampion: Successfully complete all Bizzaro mini-games
Globe Bowling: Pick up the Daily Planet globe
Kitten Finder Extraordinaire: Rescue all 100 kittens
Meteor Mayhem: Successfully complete Level 1
Outstanding Valet: Pick up 500 cars
Photo Finish: Defeat 500 opponents

Developer memorial
In Research Park, by the Superman statue, there is a memorial to Derek Allman, one of the developers. The game is dedicated to the memory of him as said in the credits.